In order to expand hepatitis C virus (HCV) screening, a change in the diagnostic paradigm is warranted to improve accessibility and decrease costs, such as utilizing dried blood spot (DBS) collection. In our study, blood from 68 patients with chronic HCV infection was spotted onto DBS cards and stored at the following temperatures for one week: −80 °C, 4 °C, 21 °C, 37 °C, and alternating 37 °C and 4 °C; to assess whether temperature change during transportation would affect sensitivity. Sample was eluted from the DBS cards and tested for HCV antibodies (HCV-Ab) and HCV core antigen (core-Ag). HCV-Abs were detected from 68/68 DBS samples at −80 °C, 4 °C, 21 °C, and 67/68 at 37 °C and alternating 37 °C and 4 °C. Sensitivity of core-Ag was as follows: 94% (−80 °C), 94% (4 °C), 91% (21 °C), 93% (37 °C), and 93% (37 °C/4 °C). Not only did temperature not greatly affect sensitivity, but sensitivities are higher than previously reported, and support the use of this assay as an alternative to HCV RNA. We then completed a head-to-head comparison (n = 49) of venous versus capillary samples, and one versus two DBS. No difference in core-Ag sensitivity was observed by sample type, but there was an improvement when using two spots. We conclude that HCV-Abs and core-Ag testing from DBS cards has high diagnostic accuracy and could be considered as an alternative to HCV RNA in certain settings.

Dried blood spots (DBS) are commonly used for serologic testing for viruses and provide an alternative collection method when phlebotomy and/or conventional laboratory testing are not readily available. DBS collection could be used to facilitate widespread testing for SARS-CoV-2 antibodies to document past infection, vaccination, and potentially immunity. We investigated the characteristics of Roche’s Anti-SARS-CoV-2 (S) assay, a quantitative commercial assay for antibodies against the spike glycoprotein. Antibody levels were reduced relative to plasma following elution from DBS. Quantitative results from DBS samples were highly correlated with values from plasma (r² = 0.98), allowing for extrapolation using DBS results to accurately estimate plasma antibody levels. High concordance between plasma and fingerpick DBS was observed in PCR-confirmed COVID-19 patients tested 90 days or more after the diagnosis (45/46 matched; 1/46 mismatched plasma vs. DBS). The assessment of antibody responses to SARS-CoV-2 using DBS may be feasible using a quantitative anti-S assay, although false negatives may rarely occur in those with very low antibody levels.

BACKGROUND: Two remote First Nations communities each collaborated with an urban-based liver clinic to organize wide-spread testing, followed by linkage to care for hepatitis C virus (HCV). METHOD: Involvement of community members was central to planning and conduct of the programs. Samples were obtained using dry blood spot cards (DBS). A week-long pilot study in Community 1 investigated the effectiveness of the program, using DBS. Community 2, being larger, more remote, and known to be endemic for HCV was more challenging. Three-week-long testing drives plus a stand-alone testing day were used to collect samples over 5 months. Public Health Agency (PHAC)’s National Laboratory for HIV Reference Services (NLHRS) received and tested the DBS samples for HCV and other blood-borne infections. Outcomes were measured by number of people tested, the quality of the tests, and community members’ satisfaction with the program and retained knowledge about HCV, based on interviews. RESULTS: In Community 1, 226 people were tested for HCV over 4 days. 85% agreed to human immunodeficiency virus (HIV) testing as well. In Community 2, 484 people, one-half of the adult population, were tested. Surveys of participants showed food was the most significant draw, and Facebook the most effective way to inform people of the events. Interviews with staff and participants showed a high level of satisfaction. CONCLUSION: The results suggest this is an effective approach to testing for HCV in unusually challenging settings. Lessons from the program include the power of community involvement; and the effectiveness of a highly targeted health initiative when developed through collaboration.

Health care initiatives, such as hepatitis C virus (HCV) screening, have been greatly overshadowed by the corona virus disease 2019 (COVID-19) pandemic. However, COVID-19 vaccination programs also provide an opportunity to engage with a high volume of people in a health care setting. We collaborated with a large COVID vaccination center to offer HCV point-of-care testing followed by dried blood spot collection for HCV RNA. Additionally, this opportunity was used to evaluate the practical significance of a 5-minute version of the OraQuick HCV antibody test in lieu of the standard 20-minute test. We tested 2317 individuals; 31 were HCV antibody positive and six were RNA positive of which four were treated and reached sustained virological response. Over a third of those surveyed said they would not have participated had the test required 20 minutes. Conclusion: Colocalizing HCV testing and linkage to care at a COVID vaccination clinic was found to be highly feasible; furthermore, a shortened antibody test greatly improves the acceptance of testing.

Background: Post-acute sequelae of COVID-19, or long COVID, is a condition characterized by persistent COVID-19 symptoms. As long COVID is defined by clinical criteria after an elapsed period, an opportunity for early intervention may aid in future prophylactic approaches; however, at present, the pathobiological mechanisms are multifactorial. By analyzing early virally infected upper respiratory tract tissue prior to eventual clinical diagnosis, it may be possible to identify biomarkers of altered immune response to facilitate future studies and interventions. Methods: This is a sub-group analysis of samples collected from those with confirmed COVID-19. RNA extraction from nasopharyngeal/mid-turbinate samples, sequencing, and bioinformatic analysis were performed to analyze long COVID and non-long COVID cohorts at day 14 post infection. Differences in mean viral load at various timepoints were analyzed as well as serological data. Results: We identified 26 upregulated genes in patients experiencing long COVID. Dysregulated pathways including complement and fibrinolysis pathways and IL-7 upregulation. Additionally, genes involved in neurotransmission were dysregulated, and the long COVID group had a significantly higher viral load and slower viral clearance. Conclusions: Uncovering early gene pathway abnormalities associated with eventual long COVID diagnosis may aid in early identification. We show that, post acute infection, in situ pathogenic deviations in viral response are associated with patients destined to meet consensus long COVID diagnosis that is entirely dependent on clinical factors. These results identify an important biological temporal window in the natural history of COVID-19 infection and long COVID pathogenesis amenable to testing from standard-of-care upper respiratory tract specimens.